2006 Mercury Mountaineer engine overheat

For vehicles with overflow coolant systems with a non-pressurized cap
on the coolant recovery system, add coolant to the coolant recovery
reservoir when the engine is cool. Add the proper mixture of coolant and
water to the “FULL COLD” level. For all other vehicles, which have a
coolant degas system with a pressurized cap, or if it is necessary to
remove the coolant pressure relief cap on the radiator of a vehicle with
an overflow system, follow these steps to add engine coolant.
To reduce the risk of personal injury, make sure the engine is
cool before unscrewing the coolant pressure relief cap. The
cooling system is under pressure; steam and hot liquid can come out
forcefully when the cap is loosened slightly.
1. Before you begin, turn the engine off and let it cool.
2. When the engine is cool, wrap a thick cloth around the coolant
pressure relief cap on the coolant reservoir (a translucent plastic bottle).
Slowly turn cap counterclockwise (left) until pressure begins to release.
3. Step back while the pressure releases.
4. When you are sure that all the pressure has been released, use the
cloth to turn it counterclockwise and remove the cap.
5. Fill the coolant reservoir slowly with the proper coolant mixture (see
above), to within the “COLD FILL RANGE” or the “FULL COLD” level on
the reservoir. If you removed the radiator cap in an overflow system, fill
the radiator until the coolant is visible and radiator is almost full.
6. Replace the cap. Turn until tightly installed (until “clicks” are heard).
(Cap must be tightly installed to prevent coolant loss.)
After any coolant has been added, check the coolant concentration, refer
toChecking engine coolantsection. If the concentration is not 50/50
(protection to –34° F/–36° C), drain some coolant and adjust the
concentration. It may take several drains and additions to obtain a 50/50
coolant concentration.
Whenever coolant has been added, the coolant level in the coolant
reservoir should be checked the next few times you drive the vehicle. If
necessary, add enough 50/50 concentration of engine coolant and
distilled water to bring the liquid level to the proper level.
If you have to add more than 1.0 quart (1.0 liter) of engine coolant per
month, have your authorized dealer check the engine cooling system.
Your cooling system may have a leak. Operating an engine with a low
level of coolant can result in engine overheating and possible engine
damage.
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Recycled engine coolant
Ford Motor Company does NOT recommend the use of recycled engine
coolant in vehicles originally equipped with Motorcraft Premium Gold
Engine Coolant since a Ford-approved recycling process is not yet
available.
Used engine coolant should be disposed of in an appropriate
manner. Follow your community’s regulations and standards for recycling
and disposing of automotive fluids.
Coolant refill capacity
To find out how much fluid your vehicle’s cooling system can hold, refer
toRefill capacitiesin this section.
Fill your engine coolant reservoir as outlined inAdding engine coolant
in this section.
Severe climates
If you drive in extremely cold climates (less than –34° F [–36° C ]):
•It may be necessary to increase the coolant concentration
above 50%.
•NEVER increase the coolant concentration above 60%.
•Increased engine coolant concentrations above 60% will
decrease the overheat protection characteristics of the engine
coolant and may cause engine damage.
•Refer to the chart on the coolant container to ensure the
coolant concentration in your vehicle will provide adequate
freeze protection at the temperatures in which you drive in the
winter months.
If you drive in extremely hot climates:
•It is still necessary to maintain the coolant concentration
above 40%.
•NEVER decrease the coolant concentration below 40%.
•Decreased engine coolant concentrations below 40% will
decrease the corrosion protection characteristics of the engine
coolant and may cause engine damage.
•Decreased engine coolant concentrations below 40% will
decrease the freeze protection characteristics of the engine
coolant and may cause engine damage.
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•Refer to the chart on the coolant container to ensure the
coolant concentration in your vehicle will provide adequate
protection at the temperatures in which you drive.
Vehicles driven year-round in non-extreme climates should use a 50/50
mixture of engine coolant and distilled water for optimum cooling system
and engine protection.
What you should know about fail-safe cooling (4.6L V8 engine
only)
If the engine coolant supply is depleted, this feature allows the vehicle to
be driven temporarily before incremental component damage is incurred.
The “fail-safe” distance depends on ambient temperatures, vehicle load
and terrain.
Fail-safe cooling and engine oil overheat mode (4.6L V8 only)
If the engine coolant and/or engine oil overheat, the vehicle’s fail-safe
modes will reduce engine power to limit engine damage, even with a
total loss of coolant. The vehicle’s range and/or speed will be reduced,
depending on vehicle load, terrain, and outside temperatures.
The instrument cluster provides warnings for each mode.
•Fail-Safe Cooling Mode:The
(Service engine
soon),
(Engine oil pressure), and(Engine coolant
temperature) indicators will be on.
Along with these warning indicators, the engine coolant temperature
gauge will read in the Hot (H) area.
If the engine coolant reaches even hotter temperatures, fail-safe
cooling mode limits engine power more and disables air conditioning.
The engine will switch to alternating cylinder operation to help cool
the engine. The engine will run rough in this mode.
If continued operation increases the engine coolant temperature to a
critical range, the engine will shut down. Steering and braking effort
will increase. Once engine coolant temperature cools, the engine can
be restarted.
•Engine Oil Overheat Mode:The
(Engine coolant temperature)
indicator will be on. The instrument cluster has no separate oil
temperature indicator.
Along with the
(Engine coolant temperature) indicator, the engine
coolant temperature gauge will read in the Hot (H) area.
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Oil overheat can be triggered in severe driving conditions, such as
towing heavy loads over mountainous terrain in extreme hot
temperatures. As oil temperature increases, engine and vehicle speed
will be limited. The transmission will also shift differently.
When the engine oil has cooled, the vehicle will perform normally.
When fail-safe cooling mode is activated
You have limited engine power when in the fail-safe mode, so drive the
vehicle with caution. Remember that the engine is capable of completely
shutting down automatically to prevent engine damage, therefore:
1. Pull off the road as soon as safely possible and turn off the engine.
2. Arrange for the vehicle to be taken to an authorized dealer.
3. If this is not possible, wait approximately 15 minutes for the engine to
cool.
4. Check the coolant level and replenish if low. Look for coolant leakage
in the engine compartment and under the vehicle.
Never remove the coolant reservoir cap while the engine is
running or hot.
5. Restart the engine and take your vehicle to an authorized dealer.
Driving the vehicle without repairing the engine problem
increases the chance of engine damage. Take your vehicle to an
authorized dealer as soon as possible.
FUEL FILTER
For fuel filter replacement, see your authorized dealer. Refer to
scheduled maintenance informationfor the appropriate intervals for
changing the fuel filter.
Replace the fuel filter with an authorized Motorcraft part. The
customer warranty may be void for any damage to the fuel system
if an authorized Motorcraft fuel filter is not used.
WHAT YOU SHOULD KNOW ABOUT AUTOMOTIVE FUELS
Important safety precautions
Do not overfill the fuel tank. The pressure in an overfilled tank
may cause leakage and lead to fuel spray and fire.
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